Simultaneous Determination of Brilliant Green and Basic Fuchsin by Cloud Point Extraction–scanometry

Abstract

In this study, cloud point extraction‒scanometry as a new, simple and inexpensive method was developed for the separation, preconcentration and determination of trace amounts of brilliant green (BG) and basic fuchsin (BF) in mixture. The method is based on the extraction of analytes simultaneously from aqueous solution using a non-ionic surfactant Triton X-114 as a cloud point extractor. After phase separation, the surfactant-rich phase was diluted with ethanol, digital image of the solution taken with a flatbed scanner and RGB parameters of the enriched analytes were calculated by special software written in visual basic (VB 6). The influence of analytical parameters including pH of system, the concentration of the surfactant, equilibration temperature and time were optimized. The method was linear in the concentration ranges of 0.025‒1.00 and 0.05‒2.50 mg/L with limits of detection of 0.008 and 0.019 mg/L for BG and BF, respectively. The preconcentration factors were 29 for BG and 28 for BF. The enrichment factors were found to be 34 and 16, precision (RSD, %) of the method, 1.9 and 1.3% for BG and BF, respectively. The effects of interfering ions and dyes were investigated. Finally, the proposed method was applied for the determination of BG and BF in real water samples with satisfactory results.